Module for screening or diverting particulate material and method of producing the module
A module is provided for screening or diverting particulate material. A method for producing a module for screening or diverting particulate material is also provided. Each module comprises either a screening member having an array of sieve apertures of a predetermined size defined therein for allowing particulate material up to the predetermined size to pass through the module or a diverting member or redirecting the flow path of the particulate material. A plurality of posts removably and interlockingly supports at least one reinforcing support frame and at least one module. Each reinforcing support frame is interlockably mounted onto the posts, and is readily detachable therefrom. Each module is disposed on the interlocking posts and is mounted onto, and readily detachable from, the reinforcing support frame. Each module is further positioned on the frame such that any particulate material passing through the module passes through the frame.
Latest Western Wire Works, Inc. Patents:
- Module for screening or diverting particulate material and method of producing the module
- Screening system for screening or diverting particulate material
- Screening systems and methods for screening particulate material
- Screening systems and methods for screening particulate material
- Screening systems and methods for screening particulate material
This is a divisional of U.S. Ser. No. 09/904,197, filed on Jul. 11, 2001, now U.S. Pat No. 6,886,697, which is a continuation application of U.S. Ser. No. 09/503,961, filed on Feb. 14, 2000, now U.S. Pat. No. 6,267,246.
BACKGROUND OF THE INVENTIONThis invention relates to modules for screening particulate material by size, or for diverting the particulate material, to methods of producing such particulate material screening systems, and to reinforcing support frames for such screening modules.
Various modes for connecting a screening module to an underlying frame to form a screening deck are known in the prior art. Some methods require spacers or adapter bars between the screening module and the deck support structure. An example of such an arrangement is shown in U.S. Pat. No. 4,409,099 (“the '099 patent”). The '099 patent shows screening modules supported only at their corners on spacer modules so that the screening element is spaced above the support structure, ostensibly to increase the effective screening area. The intermediate spacer elements, however, add considerably to the cost and complexity of the screening apparatus and increase its overall height. In addition, in order to reduce abrasion by the sifted particulate material to the support structure members, the support members must be specially formed. That requirement represents another expensive departure from standard practices in the industry.
Another screening apparatus that employs specialized components to intermediate the screening elements and the support structure is shown in U.S. Pat. No. 4,219,412 (“the '412 patent”). There, a molded plastic support frame is adapted to receive individual screening elements. The plastic frame, in turn, is connected to the deck support bars. This combination leads to several disadvantages similar to the device of the '099 patent mentioned above. The '412 patent does not disclose whether or how individual screening modules might be removed and replaced.
Similarly, U.S. Pat. No. 4,661,245 (“the '245 patent”) shows a screening system that incorporates clamping bars which receive the individual screening elements. The clamping bars, in turn, are bolted onto the support bars. The resulting structure is unduly complex, expensive, and increases the height of the deck, among other shortcomings.
Several other methods are known for connecting flat screening elements directly to a supporting frame, thereby avoiding the use of spacers or adapter bars. One such method uses a depending hook or skirt member integrally formed in the outlet side of the screening element. An example is shown in U.S. Pat. No. 3,980,555 (“the '555 patent”). In the '555 patent, depending hooks of abutting screening elements are inserted into a frame member through a common mounting hole. The hooks extend out of the mounting hole in the underside of the frame and engage the frame member to hold the screening elements in place. The resulting screening deck has a substantially contiguous inlet surface that provides no access to the mounting hooks for disconnecting an element which requires replacement. Accordingly, such arrangement requires a user to climb under a screening deck and cut the depending hooks off of a module to be replaced. Or, more commonly, a user will pry the element off from the top (inlet side) and destroy it in the process. Either way, the module is rendered useless; a result that is acceptable for modules which are worn out, but wasteful if the module is being replaced merely to change sieve size.
Another attachment method is shown in the '412 patent, discussed above. Individual screening elements are connected to an intermediate supporting frame by integrally formed depending hook-shaped members, similar to those disclosed in the '555 patent. The depending hook members are inaccessible even from the outlet side of the screen, however, as they are enclosed within elongate U-shaped channels. The '412 patent does not disclose any way of removing an individual screening element for replacement, short of disassembling the screening deck.
Another method of connecting screening elements to an underlying frame is to employ securing pins as suggested, for example, in U.S. Pat. No. 4,141,821 (“the '821 patent”). According to the '821 patent, abutting screening elements each include hollow tubular protrusions extending through a common mounting aperture formed in the frame so as to define a hollow tube. A securing pin is inserted into the tube from the inlet side of the deck to spread the protrusions apart beneath the aperture and thereby engage the frame. The securing pin is difficult to pry out of the tube from the inlet side of the screen, although the pin could, perhaps, be driven out from the outlet side of the screen. In any event, once removed, the pin is loose and therefore subject to loss. This is a decided risk in the context of screening machines, as it often is impractical or impossible to retrieve an errant securing pin. A similar securing pin is employed in the apparatus disclosed in the '099 patent discussed previously.
An improved screening system developed by the common assignee of this patent application is provided in U.S. Pat. No. 5,049,262 (“the '262 patent”). The screening system disclosed in the '262 patent includes a rigid frame and a plurality of screening modules. A lock pin is provided which detachably connects the screening modules to the rigid frame. The lock pin is designed so that it remains connected to the frame while allowing removal of the screening modules from the frame, and positioning of a replacement screening module on the frame.
Yet another apparatus for removably mounting screening elements is disclosed in U.S. Pat. No. 4,670,136 (“the '136 patent”). The '136 patent discloses a two-piece elongate clamping element for clamping the edge of a plastic module or wire mesh screen. The apparatus includes a first, lower plastic profile fastened to the load-bearing substructure and arranged to engage under the edges of at least two mutually adjacent screen elements. A second, upper profile is detachably fastened over the first lower profile for retaining the screen elements clamped in place. Removal of a screening element requires removal of the upper plastic profile, thereby subjecting it to risk of loss like the securing pins of the '821 patent and the like. Additionally, the clamping structures of the '136 patent extend substantially beyond the edges of the frame, thereby reducing the effective screening area and subjecting the clamping structure itself to excessive wear from abrasion by particulate material being screened.
Another class of modular screen systems is represented by European Patent No. 167,999 (“EP '999”) and DE 3606-854 (“DE '854”). More specifically, EP '999 is directed to a modular screen system which includes an assembly for attaching sieve elements to a metal support girder. The attachment assembly comprises upper and lower profile sections, and a protective ledge. The upper profile section engages the entire side portion of the sieve elements, while the lower profile section is connected within a continuous slot in the metal support girder. The upper profile can have a bolt-shaped cross-sectional configuration. The protective ledge covers the entire top surface of the support girder to prevent wear from abrasive material passing through the sieve elements. Since the upper profile section is in locking engagement with the entire extent of the side of the sieve element, it is extremely difficult and time consuming for users to remove and replace individual damaged screen modules. Furthermore, this removal process often results in unwanted destruction of adjacent undamaged screen modules.
U.S. Pat. No. 4,674,251 (“the '251 patent”) is directed to a screen component for use in modular screening decks. The screen comprises a frame-shaped molding which surrounds one or more fields having screening openings. At least two of the opposite sides of the molding have supporting members with fastening elements between which reinforcement rods are embedded in the molding extends. Premolding inserts are also embedded in the supporting members and have insert openings on the sides of the inserts facing each other, into which the ends of the reinforcement rods are inserted.
U.S. Pat. No. 5,372,261 (“the '261 patent”) and the '262 patent each relate to a system for screening particulate materials including replaceable screening modules mounted to a rigid frame by lock pins. An internal rigid frame member is typically provided within the module to stiffen it and prevent deformation thereof in the flow direction caused by the weight of particulate material. The lock pins are interlockingly engaged within attachment apertures of the modules.
U.S. Pat. No. 5,377,846 (“the '846 patent”) relates to a screen system having screen panel modules supported side-by-side and/or end-to-end by a support structure assembly. The reinforced renditions of these modules are typically strengthened using a discrete reinforcing bar located therein.
U.S. Pat. No. 5,755,334 (“the '334 patent”) describes an apparatus for mounting a panel on a rail member. Reinforced panels of the '334 patent also include discrete internal reinforcing members.
All of the patents cited above are incorporated in their entirety and by this reference made a part hereof.
In prior art systems when a screening module has become worn out and must be replaced, the old module must be disposed of and preferably recycled. Many reinforced screening modules of the prior art, however, have various types and configurations of discrete internal reinforcing members, which can cause a substantial recycling problem. For example, those screening modules having an internal reinforcing member are much more difficult and costly to dispose of than screening modules formed of two very different materials of constructions, for example, a polymeric module panel and a metal reinforcing member, which undergo different recycling processes. Therefore, the polymeric material portion of the reinforcing member must be separated from the metallic frame before recycling. Unfortunately, the metallic reinforcement is difficult to separate from the remaining polymeric portion of the screening module panel. This means that any recycling process for the above-described reinforced module will be time consuming and expensive.
Additionally, prior art screening polymeric modules having metallic reinforcement must be replaced in their entirety when the polymeric material becomes worn. There is no practical way to replace the polymeric material without also replacing the metallic reinforcing member, even though the reinforcing member can have a substantially longer useful life.
It is important that modules are readily secured during use to a deck assembly but can be easily removed therefrom when repair or replacement of a module is required. Both of these requirements are needed in order to provide maximum functionality of the system.
Accordingly, there remains a need for a particulate screening or diverting module which avoids the problems and meets the needs described above.
SUMMARY OF THE INVENTIONAccording to the needs of the industry, one object of the present invention is to provide a module for screening or diverting particulate material which allows for easy and quick attachment between to, for example, the underlying support members of a deck assembly.
Another object of the present invention is to provide such a module which facilitates ready attachment and removal from the deck assembly without causing damage or destruction to that module or adjacent screening modules.
To accomplish the objects of this invention, a module for screening, or diverting, particulate material is provided. The module is part of a system which includes at least one module, preferably a screening module, more preferably a non-reinforced module, and at least one reinforcing support frame, all of which are supported on a plurality of posts.
Each screening module comprises a screening member having an array of sieve apertures of a predetermined size. The sieve apertures allow passage of particulate material up to the predetermined size. Each screening module is positioned on a support frame so that particulate material passing through the screening module also passes through the frame. Each reinforcing support frame is readily and expeditiously, interlockably mounted onto, and detachable from, the posts. Each module is also interlockably mounted onto, yet readily detachable from, a structural support frame.
Each frame and the module can be formed of any suitable material. However, the frame is preferably formed of a polymeric or metallic material. The module is preferably non-reinforced so that the reinforcing support frame is substantially the sole means of reinforcement. More preferably, the module is formed of a polymeric material, which can be of a reinforcing or a non-reinforcing type.
The posts are mounted either directly or indirectly to the underlying support members of a deck assembly. Preferably, the posts are integrally joined to a mounting piece, which in turn is attached to underlying support members of the deck assembly. Typically, this type of attachment is facilitated through feet on the middle and end posts. The posts can also be joined directly to the underlying support members, without the use of a mounting piece. Each post includes one or more slots and/or recesses for interlockingly engaging with one or more modules, and a frame slot within which one or more frames are readily and interlockingly mountable. The frame slot can be arcuate-shaped to receive and engage an arcuate-shaped corner of the frame. Each post can be designed to interlocking support a plurality of screens and a plurality of support frames so that, for example, at least a portion of the particulate materials can be subject to more than one screening step.
Each module includes an engagement member which readily and interlockably mounts onto a support frame. Preferably, a portion of the engagement member has a gripping surface for engaging a complementary gripping surface located in the support frame. The gripping surfaces provide increased frictional engagement between the frame and the module. It also substantially prevents fines generated in the screening process from being entrapped between the screening module and it's supporting members. In this way, fines entrapment can substantially be avoided, so that excessive wear will be minimized, thereby failure of the locking connection between the module and the support frame assembly will be maintained for an extended period of time.
A method for producing a system for screening or diverting particulate material is also provided. The method includes providing a plurality of posts, at least one reinforcing support frame, and at least one module, preferably a non-reinforced module, more preferably a screening module, as described above. Each frame is interlockingly and detachably mounted onto the posts, and each module is interlockingly and detachably mounted onto the support frame. Each module is disposed over at least a portion of one of the posts, and positioned on the frame so that particulate material passing through the module also passes through the frame.
The novel posts of this invention provide for effective attachment to, and detachment from, both at least one module and at least one reinforcing support frame, and to the machine deck assembly. The locking engagement between each module and the posts provides for secure attachment, yet also allows easy removal without damage to the module itself or to other modules.
The invention also avoids the problem of lost securing pins, which occurs during the process of attachment and detachment of modules to the deck assembly in many prior art systems. Because the posts of the present invention are securely fastened to the deck assembly, either directly or through a mounting piece, rather than being held in place between adjacent connected modules, the lost securing pin problem can be avoided. Lost pins or the like can cause blockages resulting in substantial additional expense to the user.
The provision of separate and distinct screening modules and reinforcing support frames avoids other significant problems encountered in the prior art. Specifically, this invention allows a module to be readily attached to or removed from a support frame without removing the frame from the deck assembly. A new module can then be positioned over the existing support frame. This is particularly advantageous where the module has worn out, yet the support frame has a considerable amount of useful life remaining. Particulate penetration causes chaffing of many prior art clamping and support structures, which turn endangers the engagement therebetween.
Furthermore, the provision of modules which are separate from the support frame allows for simple, inexpensive recycling of worn or damaged parts. The module and support frame can be made of two different materials without hindering recycling efforts. Because the module and support frame are easily separated from each other, the module can undergo a recycling process adapted for that particular material, and the support frame can undergo a separate recycling process adapted for its particular material. This invention therefore allows for faster and cheaper recycling have worn or damaged components.
The unique construction of the system of the present invention typically forms screening modules having a reduced weight as compared to screening modules which include, for example, metallic reinforcement. The reduced weight screening modules of the present invention exhibit noise reduction during use and are more energy efficient. Furthermore, there are not corrosion problems and the deck weight reduction makes a significant savings in power employed by the end user.
The foregoing and other objects, features and advantages of the invention will become more readily apparent from the following detailed description of a preferred embodiment, which proceeds with reference to the drawings.
Referring now to
A preferred embodiment of the particulate screening system of this invention includes a wall mounting post assembly 4 (or 4′ in the multi-screen version of an alternative embodiment) having one or more half posts 10A, one or more quarter posts 10A′, and one or more wall mounting pieces 14A. Bolts secure each wall-mounting piece 14A to the sidewall 50 through boltholes 25. The shield 22 is connected to the wall-mounting piece 14A by being interlockingly snap fit into holes 24. Additional post assemblies 6 or 6′ (multi-screen version) are secured to support members 16 and end support members 16A in the deck assembly. The posts at each end of the post assemblies 6 or 6′ are half posts 10′ for mating with half posts 10′ at the ends of other post assemblies or with an end wall of the deck. The posts located along the mounting piece 12 between the half posts 10′ are full posts 10. The center full post 10 and half posts 10′ on the post assembly have post feet 11 and half feet 11′, respectively, for mounting to either a support member 16 or an end support member 16A.
Reinforcing support frames 18 are placed over the post assemblies such that each frame 18 is secured between four posts. Each of the four posts may be either a full post 10, a half post 10A or 10′, or a quarter post 10A′. Screening modules 20 are placed over the frames 18 and lockably, yet removably, secured thereto. The screening modules are also provided with post engagement members for interlockingly, yet detachably, securing the screening module to the posts. These post engagement members preferably include receptacles for receiving and engaging a portion of the posts and/or detents, which are inserted into and removably retained by a slot or recess in the post. In a preferred embodiment, a receptacle receives a portion of the post and an extension interlockingly engages a slot or recess in the post head. Each screening module 20 therefore lockably, yet removably, engages with each of the four posts to which its corresponding reinforcing support frame 18 is attached. The individual modules of the overall deck assembly will now be described in more detail.
Referring to
Now referring to
Referring to
Referring to
Referring to
Referring to
Now referring to
Referring to
Referring to
Now referring to
Of course, the two attachment methods described with reference to these preferred embodiments are but two of the many possible embodiments of the present invention. It should be appreciated by those skilled in the art that any method of engagement between the frame engagement members of the screening modules and the engagement surfaces of the support frame is contemplated, so long as it provides for ready, secure attachment and easy separation of the module and frame. Other potential embodiments, for instance, can comprise a tab and recess snap fit, an interference fit, or a toothed engagement. Other means and methods of securing a readily detachable locking engagement between the screening module and the frame are also within the contemplation of this invention.
Having illustrated and described the principles of my invention in a preferred embodiment thereof, it should be readily apparent to those skilled in the art that the invention can be modified in arrangement and detail without departing from such principals. I claim all modifications coming within the spirit and scope of the accompanying claims.
Claims
1. A module for screening or diverting particulate material comprising either one of a screening member having a unitary, single-level structure including an array of sieve apertures of a predetermined size defined therein for allowing particulate material up to the predetermined size to pass through the module or a diverting member having a unitary, single-level structure for redirecting the flow path of the said particulate material, the screening and diverting member including a frame engagement member, extending downwardly from a lower surface of the screening or diverting member, for interlockingly mounting the screening or diverting member onto a reinforcing support frame such that the screening or diverting member is readily attachable to and detachable therefrom, and such that particulate material passing through the screening member passes through the reinforcing support frame, the screening or diverting member comprising a substantially rectangular shape having a plurality of corners and being further interlockingly mountable onto a plurality of posts such that the screening or diverting member is readily detachable therefrom, wherein each said post is substantially connected to a single corner of the screening or diverting member, wherein said posts are spaced from said frame engagement member.
2. A module according to claim 1, wherein said screening or diverting member and said frame are configured to mate with a portion of each of said posts by snap-fit engagement.
3. A module according to claim 1, wherein said posts have a substantially circular cross-sectional configuration.
4. A module according to claim 1, wherein at least a portion of a surface of said screening or diverting member includes a gripping surface for engaging a complementary gripping surface on an engagement surface of said frame, thereby providing increased frictional mating engagement between said screening or diverting member and said frame.
5. A module according to claim 1, wherein each of said posts is joined to a mounting piece.
6. A module according to claim 5, wherein said mounting piece comprises a structural bar, a rod, or a tube.
7. A module according to claim 1, wherein each said frame engagement member comprises at least one detent member.
8. A module according to claim 1, wherein the portion of the screening member defining the array of sieve apertures, or the portion of the diverting member redirecting the flow path of the said particulate material, is formed of at least one polymeric material.
9. A module according to claim 7, wherein each detent member includes a locking tab.
10. A module according to claim 1, which is placed over the reinforcing support frame so that the frame engagement member extends along inwardly facing surfaces of the reinforcing support frame.
11. A module according to claim 9, wherein each locking tab engages the reinforcing support frame.
12. A module according to claim 1, which includes a substantially rectangular upper screening member.
13. A module according to claim 1, wherein said frame engagement members comprise substantially planar extensions having inwarding and outwarding facing sides.
14. A module according to claim 7, wherein said detent member includes a gripping surface for engaging a complementary gripping surface on an engagement surface of said frame.
15. A module according to claim 1, wherein said screening or diverting member defines a plurality of receptacles, each receptacle receiving and retaining a portion of each of said posts.
16. A module according to claim 1, wherein said screening or diverting member includes a frame engagement member extending from a lower surface thereof for readily and interlockably mounting said module onto at least one said frame.
17. A module according to claim 14, wherein said gripping surface on said detent member is located along its outwardly facing side.
18. A method for producing a module for screening or diverting particulate material, comprising:
- forming a module comprising either one of a screening member having a unitary, single-level structure including an array of sieve apertures of a predetermined size defined therein for allowing particulate material up to the predetermined size to pass through the module and a diverting member a unitary, single-level structure including for redirecting the flow path of the said particulate material, the screening and diverting member comprising a substantially rectangular shape having a plurality of corners and including a frame engagement member, extending downwardly from a lower surface of the screening or diverting member, for interlockingly mounting the screening or diverting member onto a reinforcing support frame such that the screening or diverting member is readily attachable to and detachable therefrom; and
- configuring said screening or diverting module for interlockingly and detachably mountability onto a reinforcing support frame and substantially connecting a single corner onto each of a plurality of pasts which removably and interlockingly support a reinforcing support frame, said module being disposable over at least a portion of at least one of the posts, wherein said posts are spaced from said frame engagement member,
- the module being positionable on the reinforcing support frame so that particulate material passing through the screening module passes through the reinforcing support frame.
19. A method according to claim 18, wherein said screening or diverting member and said frame are configured to mate with a portion of each of said posts by snap-fit engagement.
20. A method according to claim 18, wherein each of said posts have a substantially circular cross-sectional configuration.
21. A method according to claim 18, wherein at least a portion of a surface of said screening or diverting member includes a gripping surface for engaging a complementary gripping surface an an engagement surface of said frame, thereby providing increased frictional mating engagement between said screening or diverting member and said frame.
22. A method according to claim 18, wherein each of said posts is joined to a mounting piece.
23. A method according to claim 22, wherein each said mounting piece comprises a structural bar, a rod, or a tube.
24. A method according to claim 18, where each said frame engagement member comprises at least one detent member.
25. A method according to claim 18, wherein the portion of the screening member defining the array of sieve apertures, or the portion of the diverting member redirecting the flow path of the said particulate material, is formed of at least one polymeric material.
26. A method according to claim 24, wherein each detent member includes a locking tab.
27. A method according to claim 18, in which the module is placed over the reinforcing support frame so that the frame engagement member extends along inwardly facing surfaces of the reinforcing support frame.
28. A method according to claim 27, wherein each locking tab engages the reinforcing support frame.
29. A method according to claim 18, which includes a substantially rectangular upper screening member.
30. A method according to claim 18, wherein said frame engagement members comprise substantially planar extensions having inwarding and outwarding facing sides.
31. A method according to claim 24, wherein said detent member includes a gripping surface for engaging a complementary gripping surface on an engagement surface of said frame.
32. A method according to claim 18, wherein said screening or diverting member defines a plurality of receptacles, each receptacle receiving and retaining a portion of each of said posts.
33. A method according to claim 18, wherein said screening or diverting member includes a frame engagement member extending from a lower surface thereof for readily and interlockably mounting said module onto at least one said frame.
34. A method according to claim 31, wherein said gripping surface on said detent member is located along its outwardly facing side.
35. A module for screening or diverting particulate material comprising either one of a screening member having a unitary, single-level structure including an array of sieve apertures of a predetermined size defined therein for allowing particulate material up to the predetermined size to pass through the module or a diverting member having a unitary, single-level structure for redirecting the flow path of the said particulate material, the screening and diverting member including a frame engagement member extending downwardly from a lower surface of the screening or diverting member, for interlockingly mounting the screening or diverting member onto a reinforcing support frame such that the screening or diverting member is readily attachable to and detachable therefrom, and such that particulate material passing through the screening member passes through the reinforcing support frame, the frame engagement member comprising a detent extending downwardly from a lower surface of the screening or diverting member for readily and interlockingly mounting the screening or diverting member onto said frame, the screening or diverting member being further interlockingly mountable onto a plurality of posts such that the screening or diverting member is readily detachable therefrom, wherein the screening or diverting member comprises a substantially rectangular shape having a plurality of corners, wherein each said post is substantially connected to a single corner of the screening or diverting member, wherein said posts are spaced from said frame engagement member.
36. A module according to claim 35, having a substantially circular cross-sectional configuration.
3980555 | September 14, 1976 | Freissle |
4141821 | February 27, 1979 | Wolff |
4219412 | August 26, 1980 | Hassall |
4409099 | October 11, 1983 | Wolff |
4661245 | April 28, 1987 | Rutherford et al. |
4670136 | June 2, 1987 | Schmidt et al. |
4674251 | June 23, 1987 | Wolff |
4757664 | July 19, 1988 | Freissle |
4871288 | October 3, 1989 | Schmidt et al. |
4882044 | November 21, 1989 | Freissle |
4909929 | March 20, 1990 | Tabor |
5049262 | September 17, 1991 | Galton et al. |
5213217 | May 25, 1993 | Galton et al. |
5277319 | January 11, 1994 | Henry, Jr. |
5361911 | November 8, 1994 | Waites, Sr. et al. |
5372261 | December 13, 1994 | Galton et al. |
5377846 | January 3, 1995 | Askew |
5462175 | October 31, 1995 | Bokor |
5464101 | November 7, 1995 | Freissle |
5664685 | September 9, 1997 | Freissle |
5755334 | May 26, 1998 | Wojcik et al. |
5769241 | June 23, 1998 | Woodgate |
5829599 | November 3, 1998 | Woodgate |
5938042 | August 17, 1999 | Freissle et al. |
6206200 | March 27, 2001 | Gilles et al. |
6253926 | July 3, 2001 | Woodgate |
6260711 | July 17, 2001 | Woodgate |
36 06 854 | September 1987 | DE |
41 36 898 | May 1993 | DE |
0 167 999 | January 1986 | EP |
WO 90/05594 | May 1990 | WO |
74/5092 | August 1975 | ZA |
Type: Grant
Filed: Oct 2, 2003
Date of Patent: Aug 15, 2006
Patent Publication Number: 20040074821
Assignee: Western Wire Works, Inc. (Portland, OR)
Inventors: Lynn A. Russell (Scappose, OR), Terry R. Askew (South Wales), Jack Coleman Gold (West Linn, OR)
Primary Examiner: Kathy Matecki
Assistant Examiner: Jonathan R. Miller
Attorney: Marger Johnson & McCollom PC
Application Number: 10/678,421
International Classification: B07B 1/49 (20060101);